1. Technical Field
The present invention is related to flight data recorders and in particular to flight data recorders able to withstand high-g impact while having a very high data storage capacity.
2. Background Art
On-board flight data recorders, such as the "black box" crash data recorder of a commercial airliner, a typically unable to withstand impact loads significantly greater than 3,400 G's (where a G is the force exerted on a body by accelerating it at 32 feet/sec/sec). Moreover, such flight recorders have relatively low storage capacity, their purpose being to store only the last several minutes of on-board instrumentation data of a flight before a crash.
In attempting to construct a flight data recorder that can withstand extremely high impact forces (e.g., 40,000 G's), the problem is that a tape memory is relatively bulky while a semiconductor chip memory is subject to resonance shattering from high frequency high impact forces or is subject to breakage from low frequency bending of the circuit package.
An object of the present invention is to provide a sufficiently rigid support for semiconductor memory chips to protect them from bending while at the same time filtering out high frequencies which would shatter the chip. The goals of filtering out high frequency while increasing rigidity would seem to be incompatible, but both are fulfilled in the present invention. Moreover, the present invention meets the goal of extremely high memory storage capacity (e.g., 20 Megabytes).